Answer :
Answer:
The shift the threshold wavelength for photoelectric emission is 2.317 nm.
Explanation:
Given that,
Work function = 5.22 eV
Temperature = 25°C
Increased temperature = 300°C
Drop work function = 50 meV
We need to calculate the shift the threshold wavelength for photoelectric emission
Using formula of work function
[tex]W=\dfrac{hc}{\lambda}[/tex]
[tex]\lambda=\dfrac{hc}{W}[/tex]
The wavelength for initial temperature,
[tex] \lambda_{1}=\dfrac{hc}{W_{1}}[/tex]
The wavelength for final temperature,
[tex] \lambda_{2}=\dfrac{hc}{W_{2}}[/tex]
The change in wavelength is
[tex]\Delta \lambd = \lambda_{2}-\lambda_{1}[/tex]
[tex]\Delta \lambda=hc(\dfrac{1}{W_{2}}-\dfrac{1}{W_{1}})[/tex]
Put the value into the formula
[tex]\Delta \lambda=2.001\times10^{-25}(\dfrac{1}{5.17\times1.6\times10^{-19}}-\dfrac{1}{5.22\times1.6\times10^{-19}})[/tex]
[tex]\Delta \lambda=2.317\times10^{-9}\ m[/tex]
[tex]\Delta\lambda=2.317\ nm[/tex]
Hence, The shift the threshold wavelength for photoelectric emission is 2.317 nm.